Back Frame and Backlight System of Flat Panel Display Device

ABSTRACT

The present invention provides a back frame and a backlight system of a flat panel display device. The back frame includes at least two assembling pieces. The at least two assembling pieces are joined to form the back frame. The back frame further includes a bracing piece fixed to the assembling pieces and the bracing piece functions to fix a circuit board. The bracing piece includes a bracing body, a first suspension section, a first bearing section, and a first resilient bent section. The bracing body is fixed to the assembling pieces. The first suspension section extends from the bracing body toward one side of the bracing body. The first bearing section is spaced from the bracing body and extends from the first suspension section toward one side of the first suspension section. The first resilient bent section is located between the first bearing section and the bracing body and is bent from the first suspension section toward one side of the first suspension section. The first bearing section and the first resilient bent section resiliently clamp a first side edge of the circuit board. The technical solution provided by the present invention reduces the manufacturing cost of backlighting display device and also saves the expenditure of mold and overcomes the problem that a circuit board cannot be easily fixed.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to the field of displaying techniques, andin particular to a back frame and a backlight system of a flat paneldisplay device.

2. The Related Arts

The state-of-the-art liquid crystal display device comprises a frontbezel, a panel, and a backlight module, of which the backlight modulecomprises a back frame, a reflector plate, a light guide, and a lightingassembly.

Currently, a variety of display panels of different sizes are availablein the market to meet different needs of general consumers. For example,in the field of television set, the sizes of liquid crystal panelsinclude 31.5, 42, 46, 48, and 55 inches. Different back frame molds areprovided for liquid crystal planes of different sizes.

Referring to FIG. 1, FIG. 1 is a schematic view showing a conventionalback frame of liquid crystal display device. As shown in FIG. 1, theconventional back frame 10 is a unitary back frame, and it is often thata unitary back frame 10 is made with metal stamping or plastic injectionmolding. The unitary back frame 10 consumes much material and has a highmaterial cost. Further, a large-sized back frame 10 requires large-sizedstamping equipment, and the size of mold corresponding to such a backframe 10 is large and the structure complicated, making the expenditureof the back frame mold high. As a consequence, the conventional backframe is of a high cost.

SUMMARY OF THE INVENTION

The technical issue to be addressed by the present invention is toprovide a back frame and a backlight system of a flat panel displaydevice, which save material and mold cost and overcome the problem thata circuit board cannot be easily fixed.

To address the above technical issue, the present invention adopts atechnical solution that provides a back frame of flat panel displaydevice. The back frame comprises at least two assembling pieces. The atleast two assembling pieces are joined to form the back frame. The backframe further comprises a bracing piece fixed to the assembling pieces.The bracing piece functions to fix a circuit board. The bracing piececomprises a bracing body, a first suspension section, a first bearingsection, and a first resilient bent section. The bracing body is fixedto the assembling pieces. The first suspension section extends from thebracing body toward one side of the bracing body. The first bearingsection is spaced from the bracing body and extends from the firstsuspension section toward one side of the first suspension section. Thefirst resilient bent section is located between the first bearingsection and the bracing body and is bent from the first suspensionsection toward one side of the first suspension section. The firstbearing section and the first resilient bent section resiliently clamp afirst side edge of the circuit board.

Wherein, the bracing piece further comprises a second suspensionsection, a second bearing section, and a second resilient bent section,the second suspension section being spaced from the first suspensionsection and extending from the bracing body toward one side of thebracing body, the second bearing section being spaced from the bracingbody and extending from the second suspension section toward one side ofthe second suspension section, the second resilient bent section beinglocated between the second bearing section and the bracing body andextending from the second suspension toward one side of the secondsuspension section, the second bearing section and the second resilientbent section resiliently clamping a second side edge of the circuitboard that is opposite to the first side edge.

Wherein, the back frame comprises two bracing pieces and the two bracingpieces are spaced from each other to clamp different location of thefirst side edge and the second side edge of the circuit board.

Wherein, the bracing body is of step-like configuration and bridgesbetween the two assembling pieces.

Wherein, the back frame comprises at least two primary assemblingpieces, the at least two primary assembling pieces being joined to forma main frame structure of the back frame, the at least two primaryassembling piece comprising a first primary assembling piece and asecond primary assembling piece, the first primary assembling piecehaving an end forming at least two joint sections that are arranged tospace from each other in a lengthwise direction of the first primaryassembling piece, each of the joint sections having a structure matingan end of the second primary assembling piece, the first primaryassembling piece using one of the joint sections to join thecorresponding end of the second primary assembling piece.

Wherein, the joint sections comprise recesses formed in a surface of thefirst primary assembling piece and having a shape corresponding to theend of the second primary assembling piece for receiving the end of thesecond primary assembling piece.

Wherein, the joint sections comprise recesses formed in a surface of thefirst primary assembling piece, the second primary assembling piecehaving a surface forming protrusions at corresponding positions, theprotrusions being receivable in the recesses to join the first primaryassembling piece and the second primary assembling piece to each other.

Wherein, the second primary assembling piece has an end forming at leasttwo protrusions that are arranged to space from each other in alengthwise direction of the second primary assembling piece.

Wherein, the at least two primary assembling piece further comprise athird primary assembling piece and a fourth primary assembling piece,the first primary assembling piece, the second primary assembling piece,the third primary assembling piece, and the fourth primary assemblingpiece being straight linear and connected to each other in a leadingend-to-tailing end manner to form a rectangular main frame structureenclosing the back frame.

To address the above technical issue, the present invention adopts atechnical solution that provides a backlight system. The backlightsystem comprises a light source, a light homogenization mechanism, and aback frame; and the back frame carries the light source and the lighthomogenization mechanism. The back frame is a back frame of the backframe described in the above embodiments.

The efficacy of the present invention is that to be distinguished fromthe state of the art, the present invention provides a back frame and abacklight system that form a back frame through joining so as to makethe back frame simple in structure, save the material used for the backframe, and overcome the problem that a circuit board cannot be easilyfixed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view showing a conventional back frame of liquidcrystal display device;

FIG. 2 is a schematic view showing a flat panel display device accordingto a first embodiment of the present invention;

FIG. 3 is a schematic view showing a back frame of a flat panel displaydevice according to a second embodiment of the present invention;

FIG. 4 is a schematic view showing a back frame of a flat panel displaydevice according to a third embodiment of the present invention;

FIG. 5 is a schematic view showing a back frame of a flat panel displaydevice according to a fourth embodiment of the present invention;

FIG. 6 is a schematic view showing a joining structure of a flat paneldisplay device according to a fifth embodiment of the present invention;

FIG. 7 is a schematic view showing a diagonally-arranged first secondaryassembling piece mounted to a main frame structure of a flat paneldisplay device according to a sixth embodiment of the present invention;

FIG. 8 is a schematic view showing a first secondary assembling pieceand a second secondary assembling piece mounted to a main framestructure of a flat panel display device according to a seventhembodiment of the present invention;

FIG. 9 is a schematic view showing joint sections of a back frame of aflat panel display device according to an eighth embodiment of thepresent invention;

FIG. 10 is a cross-sectional view showing a first example of jointsection of FIG. 9;

FIG. 11 is a schematic view showing a joining structure of a jointsection of a back frame of a flat panel display device according to aninth embodiment of the present invention;

FIG. 12 is a schematic view showing a joining structure of a jointsection of a back frame of a flat panel display device according to atenth embodiment of the present invention;

FIG. 13 is a schematic view showing a joining structure of a jointsection of a back frame of a flat panel display device according to aneleventh embodiment of the present invention;

FIG. 14 is a schematic view showing a joint section of a back frame of aflat panel display device according to a twelfth embodiment of thepresent invention;

FIG. 15 is a schematic view showing a joint section of a back frame of aflat panel display device according to a thirteenth embodiment of thepresent invention;

FIG. 16 is a flow chart showing a method for manufacturing a back frameof a flat panel display device according to a fourteenth embodiment ofthe present invention;

FIG. 17 is a schematic view showing a flat panel display device with atouch screen according to a fifteenth embodiment of the presentinvention;

FIG. 18 is a schematic view showing a stereoscopic display deviceaccording to a sixteenth embodiment of the present invention;

FIG. 19 is a schematic view showing a plasma display device according toa seventeenth embodiment of the present invention;

FIG. 20 is a schematic view showing a portion of a back frame of a flatpanel display device according to an eighteenth embodiment of thepresent invention; and

FIG. 21 is a cross-sectional view of a bracing piece and a circuit boardof the back frame of FIG. 20.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to FIGS. 2-3, FIG. 2 is a schematic view showing a flat paneldisplay device according to a first embodiment of the present inventionand FIG. 3 is a schematic view showing a first embodiment of a backframe of a flat panel display device according to a second embodiment ofthe present invention. As shown in FIG. 2, the flat panel display device20 according to the instant embodiment comprises: a backlight system 21and a display panel 22. The backlight system 21 is arranged on a backside of the display panel 22 and supplies light to the display panel 22.

In the instant embodiment, the backlight system 21 comprises a lightsource 25, a light homogenization mechanism 24, and a back frame 23. Theback frame 23 carries the light source 25 and the light homogenizationmechanism 24. When the backlight system 21 is an edge lighting type, thelight homogenization mechanism 24 is a light guide; and when thebacklight system 21 is a direct type, the light homogenization mechanism24 is a diffuser plate. The back frame 23 comprises at least a firstprimary assembling piece and a second primary assembling piece, and thetwo of at least a first and second primary assembling pieces constitutea main frame structure 27 of the back frame 23.

Referring also to FIG. 3, the back frame 23 of the first embodimentcomprises a first primary assembling piece 261 and a second primaryassembling piece 262. The first primary assembling piece 261 has an endjoined to an end of the second primary assembling piece 262, and thefirst primary assembling piece 261 has another end joined to another endof the second primary assembling piece 262 in order to form the mainframe structure 27 of the back frame 23. The first primary assemblingpiece 261 and the second primary assembling piece 262 are both aluminumpieces or galvanized steel pieces. In the instant embodiment, the firstprimary assembling piece 261 and the second primary assembling piece 262are L-shaped.

Referring also to FIG. 4, the back frame 23 of a second embodimentcomprises a first primary assembling piece 281, a second primaryassembling piece 282, and a third primary assembling piece 283. Thethree primary assembling pieces 281, 282, and 283 are assembled andjoined to form a main frame structure 27 of the back frame 23. The threeprimary assembling pieces 281, 282, and 283 are all aluminum pieces orgalvanized steel pieces. In the instant embodiment, the first primaryassembling piece 281 is L-shaped, and the second and third primaryassembling pieces 282, 283 are straight linear.

Further, the back frame 23 further comprises secondary assembling piecesarranged inside and joined to the main frame structure 27.

A detailed description will be given to the back frame 23 of the flatpanel display device 20 according to the present invention, whichcomprises four primary assembling pieces and two secondary assemblingpieces.

Referring to FIG. 5, FIG. 5 is a schematic view showing a back frame offlat panel display device according to a fourth embodiment of thepresent invention. As shown in FIG. 5, in the instant embodiment, a backframe 23 comprises: a first primary assembling piece 231, a secondprimary assembling piece 232, a third primary assembling piece 233, afourth primary assembling piece 234, a first secondary assembling piece235, a second secondary assembling piece 236, and bracing pieces 2371,2372, 2373, 2374, 2375, 2376, and 2377. The first primary assemblingpiece 231, the second primary assembling piece 232, the third primaryassembling piece 233, and the fourth primary assembling piece 234 aresuccessively joined to each other in an end-to-end manner to constitutea rectangular main frame structure 27 of the back frame 23. The firstsecondary assembling piece 235 and the second secondary assembling piece236, serving as ancillary assembling pieces, are arranged in the mainframe structure 27 and joined to the main frame structure 27.

Specifically, an end of the first primary assembling piece 231 is joinedto an end of the second primary assembling piece 232, another end of thesecond primary assembling piece 232 is joined to an end of the thirdprimary assembling piece 233, another end of the third primaryassembling piece 233 is joined to an end of the fourth primaryassembling piece 234, and another end of the fourth primary assemblingpiece 234 is joined to another end of the first primary assembling piece231 in order to form the rectangular main frame structure 27. The firstprimary assembling piece 231, the second primary assembling piece 232,the third primary assembling piece 233, and the fourth primaryassembling piece 234 are all aluminum pieces or galvanized steel pieces.In the instant embodiment, the first primary assembling piece 231, thesecond primary assembling piece 232, the third primary assembling piece233, and the fourth primary assembling piece 234 are straight linear,yet in other embodiments, it is apparent to those skilled in the art tomake all the first primary assembling piece 231, the second primaryassembling piece 232, the third primary assembling piece 233, and thefourth primary assembling piece 234 L-shaped, or some being straightlinear and the remaining being L-shaped. For example, in FIG. 3, thefirst primary assembling piece 261 and the second primary assemblingpiece 262 are both L-shaped; in FIG. 4, the first primary assemblingpiece 281 is L-shaped, while the second and third primary assemblingpieces 282 and 283 are straight linear.

In the instant embodiment, the back frame 23 of the flat panel displaydevice 20 is formed by joining connection. As shown in FIG. 6, anillustrative example is given for the connection of an end of the firstprimary assembling piece 231 to an end of the second primary assemblingpiece 232, wherein the end of the second primary assembling piece 232 isjoined to the end of the first primary assembling piece 231 by means offor example screwing, fastening, or welding, to have the end of thesecond primary assembling piece 232 connected to the end of the firstprimary assembling piece 231.

In the instant embodiment, the first secondary assembling piece 235 andthe second secondary assembling piece 236 are arranged in the main framestructure 27 of the back frame 23. An end of the first secondaryassembling piece 235 is joined to the first primary assembling piece 231and another end of the first secondary assembling piece 235 is joined tothe third primary assembling piece 233; and an end of the secondsecondary assembling piece 236 is joined to the first primary assemblingpiece 231 and another end of the second secondary assembling piece 236is joined to the third primary assembling piece 233. Further, the secondprimary assembling piece 232, the fourth primary assembling piece 234,the first secondary assembling piece 235, and the second secondaryassembling piece 236 are arranged parallel to each other. In otherembodiments, those skilled in the art may arrange at least one secondaryassembling piece in the main frame structure 27. For example, only thefirst secondary assembling piece 235 is arranged in the main framestructure 27. Further, the two ends of the first secondary assemblingpiece 235 can be selectively joined to at least two of the primaryassembling pieces of the first primary assembling piece 231, the secondprimary assembling piece 232, the third primary assembling piece 233,and the fourth primary assembling piece 234. For example, the firstsecondary assembling piece 235 is set diagonally in the main framestructure 27, as shown in FIG. 7. Similarly, the two ends of the secondsecondary assembling piece 236 can be selectively joined to at least twoof the primary assembling pieces of the first primary assembling piece231, the second primary assembling piece 232, the third primaryassembling piece 233, and the fourth primary assembling piece 234. Forexample, the two ends of the first secondary assembling piece 235 arerespectively joined to the first primary assembling piece 231 and thesecond primary assembling piece 232 that are adjacent to each other andthe two ends of the second secondary assembling piece 236 arerespectively joined the third primary assembling piece 233 and thefourth primary assembling piece 234 that are adjacent to each other, asshown in FIG. 8.

In the instant embodiment, the back frame 23 comprises seven bracingpieces 2371, 2372, 2373, 2374, 2375, 2376, and 2377. The bracing piece2371 is fixed to the fourth primary assembling piece 234; the bracingpieces 2372, 2373 are both fixed to the first secondary assembling piece235; the bracing piece 2374 is fixed to the second secondary assemblingpiece 236; the bracing piece 2375 is fixed to the second primaryassembling piece 232; and the bracing pieces 2376, 2377 are each fixed,at two ends thereof, to the first secondary assembling piece 235 and thesecond secondary assembling piece 236. In practice, the bracing piecescan be fixed to one or more of the first primary assembling piece 231,the second primary assembling piece 232, the third primary assemblingpiece 233, the fourth primary assembling piece 234, the first secondaryassembling piece 235, and the second secondary assembling piece 236. Inother embodiments, those skilled in the art may mount bracing pieces ofany other numbers to the back frame 23, such as one or more bracingpieces. Further, the bracing pieces can be releasably fixed to one ormore of the first primary assembling piece 231, the second primaryassembling piece 232, the third primary assembling piece 233, the fourthprimary assembling piece 234, the first secondary assembling piece 235,and the second secondary assembling piece 236.

The bracing pieces 2371, 2372, 2373, 2374, 2375, 2376, and 2377 may beprovided with bumps (not labeled) so that the back frame 23 may fixcomponents, such as circuit boards, with such bumps.

Molds for making the back frame 23 will be described. In the instantembodiment, the first primary assembling piece 231 and the third primaryassembling piece 233 are of the same size and shape so that they can bemade by stamping with the same mold. The second primary assembling piece232, the fourth primary assembling piece 234, the first secondaryassembling piece 235, and the second secondary assembling piece 236 areof the same size and shape so that they can be made by stamping with thesame mold, making it possible to share the mold. Thus, the back frame 23of the present invention can be made by stamping with only twosmall-sized molds, and compared to the conventional back frame 10 thatrequires a large-sized mold, the molds for making the back frame 23 ofthe present invention are simple in structure and small in size and thusthe cost of mold for the back frame 23 can be lowered. Further, comparedto the whole back frame structure of the conventional back frame 10, theback frame 23 of the present invention can significantly save materialused and thus reduce the manufacturing cost of the flat panel displaydevice 20.

Referring to FIG. 9, FIG. 9 is a schematic view showing joint sectionsof a back frame of a flat panel display device according to an eighthembodiment of the present invention. As shown in FIG. 9, in the instantembodiment, an end of the first primary assembling piece is providedwith two joint sections, and the joint sections have a structure matingan end of the second primary assembling piece so that the first primaryassembling piece can be joined to a corresponding end of the secondprimary assembling piece.

Specifically, the first primary assembling piece 231 has an end formingjoint sections 2311, 2312, and the joint sections 2311, 2312 arearranged in a spaced manner in a lengthwise direction of the firstprimary assembling piece 231. The joint sections 2311, 2312 are formedby forming recesses having a shape mating an end of the second primaryassembling piece 232 in the first primary assembling piece 231 in orderto receive the end of the second primary assembling piece 232 therein.As shown in FIG. 10, the joint sections 2311, 2312 are recesses that donot extend through opposite surfaces of the end of the first primaryassembling piece 231 and the recesses are of a rectangular shape withthe second primary assembling piece 232 being straight linear.

To assemble a large-sized back frame 23, the joint section 2311 that isclose to the very end of the first primary assembling piece 231 is firsttaken and a second primary assembling piece 232 having a correspondingwidth is selected. Afterwards, an end of the second primary assemblingpiece 232 is positioned in the recess of the joint section 2311. Andthen, means, such as screwing, fastening, or welding, is applied to joinand fix the end of the second primary assembling piece 232 to the jointsection 2311. To assemble a small-sized back frame 23, the joint section2312 that is distant from the very end of the first primary assemblingpiece 231 is first chosen and a second primary assembling piece 232having a corresponding width is selected. Afterwards, an end of thesecond primary assembling piece 232 is positioned in the recess of thejoint section 2312. And then, means, such as screwing, fastening, orwelding, is applied to join and fix the end of the second primaryassembling piece 232 to the joint section 2312. Specifically, forexample the second primary assembling piece 232 forms a protrusion at acorresponding location on a surface thereof, and the protrusion of thesecond primary assembling piece 232 is embedded in the recess the firstprimary assembling piece 231 at a corresponding location in order tojoin the first primary assembling piece 231 and the second primaryassembling piece 232, as shown in FIG. 11. Further, the second primaryassembling piece 232 may form, on one end thereof, at least twoprotrusions that are spaced in the lengthwise direction of the secondprimary assembling piece 232, such as two, three, or four protrusions.

Furthermore, the recess of the first primary assembling piece 231 can bea recess of a multi-stepped configuration and the second primaryassembling piece 232 forms, at a corresponding location, a protrusionhaving a multi-stepped configuration corresponding to the recess, asshown in FIG. 12. Further, as shown in FIG. 13, taking the joint section2311 as an example, the recess of the first primary assembling piece 231forms, in a bottom thereof, a first through hole 2313, and the secondprimary assembling piece 232 forms, at a location corresponding to thejoint section 2311, a second through hole 2321. The back frame 23further comprises a fastener 240. The fastener 240 extends through thefirst through hole 2313 and the second through hole 2321 to joint thefirst primary assembling piece 231 and the second primary assemblingpiece 232 to each other.

As shown in FIG. 14, in another embodiment of the back frame of flatpanel display device according to the present invention, the recesses ofthe joint sections 2311, 2312 of the first primary assembling piece 231are of a circular shape. Yet, in other embodiments, those skilled in theart may arrange the shape of the recesses to be other polygonalconfigurations, such as triangle.

As shown in FIG. 15, in another embodiment of the back frame of flatpanel display device according to the present invention, the jointsections 2311, 2312 are recesses that do not extend through oppositesurfaces of the first primary assembling piece 231, whereby an end ofthe second primary assembling piece 232 is movable within the jointsections 2311, 2312. For example, after the end of the second primaryassembling piece 232 is set extending beyond and joined and fixed to thejoint section 2312, the portion of extension is then trimmed off so thatthe length of the second primary assembling piece 232 that serves as aprimary assembling piece of the back frame can be adjusted.

In a practical application, the other end of the first primaryassembling piece 231 and both ends of the third primary assembling piece233 are all provided with two joint sections having a structureidentical to that of the joint sections 2311, 2312. The ends of thesecond primary assembling piece 232 and the ends of the fourth primaryassembling piece 234 may be subjected to specific designs or no designat all according to the application. For example:

(1) In a first situation, as shown in FIG. 10, the two ends of thesecond primary assembling piece 232 and the two ends of the fourthprimary assembling piece 234 are of no specific design. In other words,the ends are of the same structure as the remaining portions. Under thiscondition, in making a join with a selected joint section 2311 (2312) atone end of the first primary assembling piece 231 (the same applicableto the other end), if an attempt is made to change the width of the backframe 23, then the length of the corresponding second primary assemblingpiece 232 and fourth primary assembling piece 234 must be selectedaccordingly. Namely, if the joint section 2311 that is close to the veryend of the first primary assembling piece 231 is selected for joining,then no trimming is applied to the second primary assembling piece 232and the fourth primary assembling piece 234 or the portion that istrimmed off is short; if the joint section 2312 that is distant from thevery end of the first primary assembling piece 231 is selected forjoining, then the second primary assembling piece 232 and the fourthprimary assembling piece 234 are trimmed and the trimmed portion beinglong or short is according to the distance that the joint section isfrom the very end of the first primary assembling piece 231 being greator small; and

(2) In a second situation, it is similar to the first situation, but asshown in FIG. 11, the second primary assembling piece 232 and the fourthprimary assembling piece 234 use different protrusions to respectivelymate the first primary assembling piece 231 and the third primaryassembling piece 233 in order to realize change of width of the backframe 23; similarly, if a joint section 2312 other than the first jointsection 2311 that is close to the very end of the first primaryassembling piece 231 is selected for joining, then before or afterjoining, excessive portions of the second primary assembling piece 232and the fourth primary assembling piece 234 may be trimmed off.

This also applicable to a main frame structure 27 of the back frame 23that is formed by joining two L-shaped primary assembling pieces.

In summary, the present invention provides a back frame 23 having afirst primary assembling piece that is provided with at least two jointsections. The number of the joint section can be selected according tothe requirement of customers. In the instant embodiment, a descriptionis given to an example comprising two joint sections 2311, 2312. Thus,to prepare the molds for making the back frame 23, only two sets of moldare needed, namely one mold for a first primary assembling piece and theother mold for a second primary assembling piece. The first primaryassembling piece may be provided with a plurality of joint sections forjoining operation in order to form various sizes for the back frame 23.To assemble the back frame 23, based on the desired size of the backframe 23, the corresponding one of the joint sections is selected. Withthe joint section, the second primary assembling piece is joined to thejoint section of the first primary assembling piece and the other jointsection of the first primary assembling piece that is located outward ofthe joining location of the second primary assembling piece is trimmedoff to obtain a desired size of the back frame 23. Compared to theconventional technology that requires different back frame molds formaking different sizes of back frame 10, the back frame of the flatpanel display device 23 according to the present invention requires onlya mold for the first primary assembling piece and a mold for the secondprimary assembling piece 28 so that mold sharing among various sizes ofproduct can be realized and the molds used are of simple structures,allowing of reduction of expenditure of the molds for back frames.

The present invention also provides a mold for making a back frame offlat panel display device. The back frame mold is provided with a mainpattern for forming a primary assembling piece of the back frame and themain pattern comprises a sub-pattern that forms at least two jointsections on an end of the primary assembling piece. The primaryassembling piece comprises the previously discussed first primaryassembling piece and second primary assembling piece, corresponding tothe above mentioned main pattern; and the joint section comprises thepreviously discussed joint section of the first primary assemblingpiece, corresponding to the above mentioned sub-pattern. Repeateddescription is omitted herein.

As shown in FIG. 16, the present invention also provides a method formaking a back frame of flat panel display device. The method comprisesthe following steps:

Step 501: manufacturing at least first and second primary assemblingpieces, in which the first primary assembling piece has an end formingat least two joint sections, each of the joint sections having astructure that mates a corresponding end of the second primaryassembling piece; and

Step 502: selecting one joint section of the at least two joint sectionsaccording to a size of the back frame to join the corresponding end ofthe second primary assembling piece.

In the instant embodiment, when other joint sections are present betweenthe joining location of the second primary assembling piece and the endof the first primary assembling piece, before or after the step ofselecting one joint section of the at least two joint sections accordingto a size of the back frame to join the corresponding end of the secondprimary assembling piece, the other joint sections of the first primaryassembling piece that are located outward of the joining position of thesecond primary assembling piece are trimmed off. The first primaryassembling piece comprises the previously discussed first primaryassembling piece, and the second primary assembling piece comprises thepreviously discussed second primary assembling piece, and repeateddescription will be omitted herein.

As shown in FIG. 17, the flat panel display device 20 of the presentinvention further comprises a touch screen 29. The touch screen 29 isarranged on a light exit surface of the display panel 22 of the flatpanel display device 20. The flat panel display device 20 comprises: thebacklight system 21 and the above discussed display panel 22. Thebacklight system 21 is arranged at the back side of the display panel 22and supplies light to the display panel 22.

The backlight system 21 comprises a light source 25, a lighthomogenization mechanism 24, and a back frame 23. The back frame 23carries the light source 25 and the light homogenization mechanism 24.When the backlight system 21 is an edge lighting type, the lighthomogenization mechanism 24 is a light guide; and when the backlightsystem 21 is a direct type, the light homogenization mechanism 24 is adiffuser plate. The back frame 23 comprises at least a first primaryassembling piece and a second primary assembling piece, and the at leastone first and second primary assembling pieces constitute a main framestructure 27 of the back frame 23.

It is noted that the flat panel display device 20 of the presentinvention can be a liquid crystal display device or a liquid crystaltelevision.

The present invention also provides a stereoscopic display device 30, asshown in FIG. 18. The stereoscopic display device 30 comprises a liquidcrystal lens grating 31, a backlight system 32, and a display panel 33.The liquid crystal lens grating 31 is arranged on a light exit surfaceof the display panel 33. The backlight system 32 can be a backlightsystem of one of the above discussed embodiments, such as the backlightsystem 32 comprising the back frame 23. The back frame 23 comprises atleast first primary assembling piece and the second primary assemblingpiece. The at least first and second primary assembling pieces form amain frame structure of the back frame. Repeated description will beomitted herein.

The present invention also provides a plasma display device 40, as shownin FIG. 19. The plasma display device 40 comprises a plasma displaypanel 41 and a back frame 42. The back frame 42 is arranged at a backside of the display panel 41. The back frame 42 can be the back frame ofany of the previously discussed embodiments and repeated descriptionwill be omitted herein.

The present invention also provides a bracing piece that is applicableto each of the above described embodiments and is fixed to theassembling pieces for fixing a circuit board. Referring to FIGS. 20-21,assembling pieces 71, 72, and 73 are the various assembling piecesdescribed in the above discussed embodiments, including the primaryassembling pieces that are joined to form a main frame structure or thesecondary assembling pieces that are arranged inside the main framestructure and joined to the main frame structure. A bracing piece 60comprises a bracing body 61, a first suspension section, a first bearingsection 63, and a first resilient bent section 64. The bracing body 61is fixed to the assembling pieces 71 and 72. In the instant embodiment,the bracing body 61 is of a step-like configuration and bridges betweenthe two assembling pieces 71, 72. However, in backup embodiments of thepresent invention, the bracing body 61 can be of a straight bar likeconfiguration or other shapes. Further, the bracing body 61 can be fixedto the assembling piece with only one end thereof, while the other endis arranged in a suspending form to simplify mounting process.

The first suspension section 62 extends from the bracing body 61 towardone side of the bracing body 61. The first bearing section 63 is spacedfrom the bracing body 61 and extends from the first suspension section62 toward one side of the first suspension section 62. The firstresilient bent section 64 is located between the first bearing section62 and the bracing body 61 and is bent from the first suspension section63 toward one side of the first suspension section 62. The first bearingsection 63 and the first resilient bent section 64 resiliently clamp afirst side edge of a circuit board 80.

Referring to FIG. 21, the bracing piece 60 further comprises a secondsuspension section 62′, a second bearing section 63′, and a secondresilient bent section 64′. The second suspension section 62′ is spacedfrom the first suspension section 62 and extends from the bracing body61 toward one side of the bracing body 61. The second bearing section63′ is spaced from the bracing body 61 and extends from the secondsuspension section 62′ toward one side of the second suspension section62′. The second resilient bent section 64′ is located between the secondbearing section 63′ and the bracing body 61 and the bracing body 61 andis bent from the second suspension section 62′ toward one side of thesecond suspension section 62′. The second bearing section 63′ and thesecond resilient bent section 64′ resiliently clamp a second side edgeof the circuit board 80 that is opposite to the first side edge. In apreferred embodiment, the first suspension section 62, the first bearingsection 63, and the first resilient bent section 64 and the secondsuspension section 62′, the second bearing section 63′, and the secondresilient bent section 64′ are symmetric with respect to a center lineof the bracing body 61. In a backup embodiment of the present invention,the bracing body 61 of the bracing piece 60 may comprise only the firstsuspension section 62, the first bearing section 63, and the firstresilient bent section 64 for only resiliently clamping the first sideedge of the circuit board 80, and an additional bracing piece that isidentical to the bracing piece 60 is provided to resiliently clamp thesecond side edge of the circuit board 80.

Referring to FIG. 21, after the circuit board 80 is mounted, anelectromagnetic shielding piece 100 is set on the bracing body 61. Theelectromagnetic shielding piece 100 is spaced from the circuit board 80to shield electromagnetic signals generated by the circuit board 80. Theelectromagnetic shielding piece 100 can be a Faraday cage or a metalplate.

Referring to FIG. 20, in the instant embodiment, a bracing piece 90 thatis identical to the bracing piece 60 is further provided. The bracingpiece 90 is spaced from the bracing piece 60 to clamp differentlocations of the first and second side edges of the circuit board 80.

With the above discussed manners, the present invention provides a backframe and a backlight system that form a back frame through joiningoperation so that the back frame is of a simple structure and thematerial used for back frame is saved to thereby lower down themanufacturing cost of flat panel display device. Further, a bracingpiece that comprises a bracing body, a first suspension section, a firstbearing section, and a first resilient bent section is used to fixe acircuit board, making it possible to save expenditure of mold andovercome the problem of being not easy to fix a circuit board.

Embodiments of the present invention have been described, but are notintending to impose any undue constraint to the appended claims of thepresent invention. Any modification of equivalent structure orequivalent process made according to the disclosure and drawings of thepresent invention, or any application thereof, directly or indirectly,to other related fields of technique, is considered encompassed in thescope of protection defined by the clams of the present invention.

What is claimed is:
 1. A back frame of a flat panel display device,wherein the back frame comprises at least two assembling pieces, the atleast two assembling pieces being joined to form the back frame, theback frame further comprising a bracing piece fixed to the assemblingpieces, the bracing piece adapted to fix a circuit board, the bracingpiece comprising a bracing body, a first suspension section, a firstbearing section, and a first resilient bent section, the bracing bodybeing fixed to the assembling pieces, the first suspension sectionextending from the bracing body toward one side of the bracing body, thefirst bearing section being spaced from the bracing body and extendingfrom the first suspension section toward one side of the firstsuspension section, the first resilient bent section being locatedbetween the first bearing section and the bracing body and being bentfrom the first suspension section toward one side of the firstsuspension section, the first bearing section and the first resilientbent section resiliently clamping a first side edge of the circuitboard.
 2. The back frame as claimed in claim 1, wherein the bracingpiece further comprises a second suspension section, a second bearingsection, and a second resilient bent section, the second suspensionsection being spaced from the first suspension section and extendingfrom the bracing body toward one side of the bracing body, the secondbearing section being spaced from the bracing body and extending fromthe second suspension section toward one side of the second suspensionsection, the second resilient bent section being located between thesecond bearing section and the bracing body and extending from thesecond suspension toward one side of the second suspension section, thesecond bearing section and the second resilient bent section resilientlyclamping a second side edge of the circuit board that is opposite to thefirst side edge.
 3. The back frame as claimed in claim 2, wherein theback frame comprises two bracing pieces and the two bracing pieces arespaced from each other to clamp different location of the first sideedge and the second side edge of the circuit board.
 4. The back frame asclaimed in claim 2, wherein the bracing body is of step-likeconfiguration and bridges between the two assembling pieces.
 5. The backframe as claimed in claim 1, wherein the back frame comprises at leasttwo primary assembling pieces, the at least two primary assemblingpieces being joined to form a main frame structure of the back frame,the at least two primary assembling pieces comprising a first primaryassembling piece and a second primary assembling piece, the firstprimary assembling piece having an end forming at least two jointsections that are arranged to space from each other in a lengthwisedirection of the first primary assembling piece, each of the jointsections having a structure mating an end of the second primaryassembling piece, the first primary assembling piece using one of thejoint sections to join the corresponding end of the second primaryassembling piece.
 6. The back frame as claimed in claim 5, wherein thejoint sections comprise recesses formed in a surface of the firstprimary assembling piece and having a shape corresponding to the end ofthe second primary assembling piece for receiving the end of the secondprimary assembling piece.
 7. The back frame as claimed in claim 5,wherein the joint sections comprise recesses formed in a surface of thefirst primary assembling piece, the second primary assembling piecehaving a surface forming protrusions at corresponding positions, theprotrusions being receivable in the recesses to join the first primaryassembling piece and the second primary assembling piece to each other.8. The back frame as claimed in claim 7, wherein the second primaryassembling piece has an end forming at least two protrusions that arearranged to space from each other in a lengthwise direction of thesecond primary assembling piece.
 9. The back frame as claimed in claim5, wherein the at least two primary assembling piece further comprise athird primary assembling piece and a fourth primary assembling piece,the first primary assembling piece, the second primary assembling piece,the third primary assembling piece, and the fourth primary assemblingpiece being straight linear and connected to each other in a leadingend-to-tailing end manner to form a rectangular main frame structureenclosing the back frame.
 10. A backlight system, wherein the backlightsystem comprises a light source, a light homogenization mechanism, and aback frame; and the back frame carries the light source and the lighthomogenization mechanism, the back frame being a back frame claimed inclaim 1.